Stencil-sheet.



7 No Drawing.

'nm'rEn s rarns "PATENT "canton.

STENCIL-SHEET.

To all whom it mag concern:

Be it known that I, LOUIS E. F LLER, a citizen of the United States, residing in the borough of vManhattan, city, county, and State of New York, have invented certain new and useful Improvements in Stencil- Sheets, of which the following is a specification.

My invention relates to stencil-sheets suit-1 able for use, for example, in addressingor duplicating-machines, for the productlon of multiple copies of writtpn or typewritten matter, diagrams, etc. Heretofore -such stencil-sheets have been made largely of ooagulated protein, and these, before being stencilized, have been moistened to soften or otherwise afiect the coated surface, to thereby facilitate the stencilizing operation. The object of the present invention is to produce a stencil-sheet which shall be normally impervious to ink, which may be stencilized without preliminary moistening, and which shall be usable throughout an extended period of time after its preparation.

In carrying out the invention in a preferred form, I employ a solution having as itsbase a colloidal substance, for example glue or gelatin of substantial jelly strength,

such as the hide glue now commonly known out moistening for an extended period! By the term fat acids I refer to the acids most frequently met with in fat, such as oleic, palmitic and stearic. This solution, prepared as hereinafter set forth more in detail, is employed as a bath, in which may be immersed sheets of a suitable basic material,-such, for example, as open porous fiber of the character of the paper commonly known as Yoshino, after such immersion the solutionbeing allowed to dry harden. Thereafter, and for a substantial period of time following its preparation, the

Specification of Letters Patent.

' shall have been swollen,

and

v LOUIS FULLER, OF NEW YORK, N. Y., ASSIGNOR TO A. B. DICK COMPANY, OF CHIOAGO, I ILLINOIS, A CORPORATION 'OF ILLINOIS.

Patented oct. 23?; 1917.

Application filed February 12, 1916. Serial No. 78,043.

stencil-sheets so formed may be stencilized in the usual manner, a. e., by placingthem in a typewriting-machine and impressing the type characters thereon by pressure. A stencil-sheet so formed may be used for the production of multiple copies in any of the well-known duplicating-machines.

' As an embodiment of my invention is a preferred form but without thereto, I shall describe the ingredients used and the steps taken in the preparation of the solution wherewiththe basic sheet is treated.

limiting myself I first, as above stated, select a glue or gelatin of substantial jelly strength (such, for example, as No. 1 hide glue), and for ease of manipulation grind the same to reasonably'small particles. To about ten grams of this ground glue, I add about forty rams of water, agitating the mixture therea ter to thoroughly wet said'particles. I then add to such mixture about forty grams of alizarin oil or Turkey-red oil, this being the material commercially on the market and so known as 50%. commercial Turkey-red oil. (If this be found to contain substantially less than fifty per cent. fat, the proportion of the whole should be slightly increased, as,

for exam le, to forty-five or fift rams.) I then a dd to the y g grams of pure oleic acid, and a solvent such as denatured alcohol to the extent of about fifty grams. The mixture should thenfib'e mixture about thirty allowed to stand until the particles of glue or to save time may be agitated for about twent -minutes. shouldthen be warmed in a w ater-bath until the particles of glue shall have become melted and the compound has become sub.- stantially homogeneous.

I next add to the solution a material which will, to some' extent, harden the solution after it shall have been the Yoshino sheet, and also vpreferably act placed upon as a preservative of the fats andioils in such solution. A suitable materialfor this purpose is ordinary, commercialformalde hyde, and of this I add, in the solution as above compounded, about five grams.

At this point, it should be remarked that? the solution should, of course, be free from-- ;all impurities and even from bubbles or foam, the latter being either allowed to evaporate or being disposed of by the addition to the solution of a few drops of either.

.above described as a preferred form of my invention may be placed in a suitable shallowpan, provided with a rod or other device adapted to remove surplus solution from the surface of the Yoshino sheet. Such sheet may be allowed to restupon the surface of the solution and then drawn over suchisurface, past the rod or other similar device, thereby removing surplus solution, and then exposed to the air, whereupon the solution will, within a comparatively short time, harden and dry, so that the sheet may thereafter be freely manipulated without the danger of cracking or injuring the-same, thereby opening interstices which would de tract from the usefulness of the sheet as a stencil.

.Also, such a sheet may be stencil-ized in the well-known manner, such, for example, as bypassing it into a Writing-machine in combination with a backing, preferably of firm hard-surfaced paper, the ribbon of the machine being removed and the type impinging directly, upon the surface of the stencil-sheet. If desirable for the purpose of obtaining broader lines in the type characters, a sheet of bolting-cloth may be inserted between the stencil-sheet and the baclning. After stencilization in the manner suggested, the sheet maybe used for the production rif multiple copies in any "suitable duplicator...

till

/Vhat ll claim is:

l. Astencil blank comprising a sheet of open porous material impregnated with a colloidal substance containing a fat acid, substantially as set forth. a

2. A stencil blank comprising a sheet of open porous material impregnated with a coagulated colloidal substance containing a fat acid distributed substantially homogenelpusly therethrough, substantially as set ort l 3. A stencil blank cbmprising a sheet of.

openporous' material impregnated with coagulated protein contag a fatacid distributed therethrough, substantially as set forth.

d A stencil blank comprising a sheet of open porous material treated with a substance including a colloid, a fat acid and formaldehyde, substantially as set forth.

5. A. stencil blank comprising a sheet of open porous material impregnated with a colloidal substance containing a fat acid and alizarin oil distributed therethrough, h substantially as set forth.

6. A stencil blank comprising a sheet of open porous material impregnated with a composition comprising coagulated protein, a fat acid and alizarin oil, substantially as set forth.

7. A stencil blank comprising a sheet of open porous material impregnated with a composition comprising a coagulated colloidal substance, oleic acid and alizarin oil,

substantially as set forth.

8. A stencil blank comprising a sheet of open porous material treated with a mixture including a colloidalsubstance, formaldehyde, a fat acid and alizarin oil, substan tially as set forth. 7

9. A stencil blank comprising a sheet of open porous material impregnated with a composition comprising coagulated protein and oleic acid, substantially as set forth. 10. A stencil blank comprising a sheet of open porous material impregnated with a composition comprising coagulated glue and oleic acid, substantially as set forth.

ii. A. stencil blank comprising a sheet of open porous material impregnated with a coagulated colloidal substance containing oleic acid distributed substantially homogeneously therethrough, substantially as set forth. 12. A stencil blank comprising a sheet of open porous material impregnated with a coagulated colloidal substance containing oleic acid and'alizarin oil distributed therethrough, substantially as set forth.

This specification signed and witnessed this 24th day of December, 1915.

Louis E. rnnnnn. 

